.dropdown,
.dropleft,
.dropright,
.dropup {
  position: relative;
}

.dropdown-menu {
  @include border-radius($menu-border-radius);
  @include text-align(left);

  background-color: transparent;
  color: inherit;
  display: none;
  float: left;
  font-size: $menu-font-size;
  font-weight: $menu-font-weight;
  line-height: $menu-line-height;
  list-style: none;
  margin: 0;
  min-width: $menu-min-width;
  padding: $menu-padding-y 0;
  position: absolute;
  top: 100%;
  left: 0;
  z-index: map-get($menu-elevation-shadow, elevation);

  &.show {
    display: block;

    &::before,
    > * {
      animation-duration: $transition-duration-mobile;
      animation-timing-function: $transition-timing-function-standard;

      @include media-breakpoint-up(sm) {
        animation-duration: $transition-duration-tablet;
      }

      @include media-breakpoint-up(lg) {
        animation-duration: $transition-duration-desktop;
      }

      @media screen and (prefers-reduced-motion: reduce) {
        animation: none;
      }
    }

    &::before {
      animation-name: dropdown-menu-show;
    }

    > * {
      animation-name: dropdown-item-show;
    }

    > :nth-child(1) {
      animation-name: dropdown-item-show-1;
    }

    > :nth-child(2) {
      animation-name: dropdown-item-show-2;
    }

    > :nth-child(3) {
      animation-name: dropdown-item-show-3;
    }
  }

  &::before {
    @include border-radius($menu-border-radius);

    background-color: $menu-bg;
    box-shadow: map-get($menu-elevation-shadow, shadow);
    content: '';
    display: block;
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    transform-origin: 0 0;
    z-index: -1;
  }

  .nav:not(.flex-column):not(.flex-column-reverse) & {
    min-width: 100%;
  }
}

.menu {
  margin-top: (($btn-height + $menu-padding-y) * -1 + ($menu-link-height - $btn-height) / -2);

  &::before {
    transform-origin: 0 ($menu-link-height / 2 + $menu-padding-y);
  }
}

.show > a {
  outline: 0;
}

.dropdown-menu-right:not([x-placement]) {
  right: 0;
  left: auto;

  &.menu::before {
    transform-origin: 100% ($menu-link-height / 2 + $menu-padding-y);
  }

  &::before {
    transform-origin: 100% 0;
  }
}

.dropleft {
  .dropdown-menu:not([x-placement]) {
    top: 0;
    right: 100%;
    left: auto;

    &.menu {
      margin-top: 0;
    }

    &::before {
      transform-origin: 100% 0;
    }
  }
}

.dropright {
  .dropdown-menu:not([x-placement]) {
    top: 0;
    left: 100%;

    &.menu {
      margin-top: 0;
    }

    &::before {
      transform-origin: 0 0;
    }
  }
}

.dropup {
  .dropdown-menu:not([x-placement]) {
    top: auto;
    bottom: 100%;

    &.menu {
      margin-top: 0;
      margin-bottom: (($btn-height + $menu-padding-y) * -1 + ($menu-link-height - $btn-height) / -2);

      &::before {
        transform-origin: 0 calc(100% - #{$menu-link-height / 2 + $menu-padding-y});
      }
    }

    &::before {
      transform-origin: 0 100%;
    }

    > :nth-child(1),
    > :nth-child(2),
    > :nth-child(3) {
      animation-name: dropdown-item-show;
    }

    > :nth-last-child(1) {
      animation-name: dropdown-item-show-1;
    }

    > :nth-last-child(2) {
      animation-name: dropdown-item-show-2;
    }

    > :nth-last-child(3) {
      animation-name: dropdown-item-show-3;
    }
  }

  .dropdown-menu-right:not([x-placement]) {
    &.menu::before {
      transform-origin: 100% calc(100% - #{$menu-link-height / 2 + $menu-padding-y});
    }

    &::before {
      transform-origin: 100% 100%;
    }
  }
}

.dropdown-menu[x-placement='bottom-end']::before,
.dropdown-menu[x-placement='left-start']::before {
  transform-origin: 100% 0;
}

.dropdown-menu[x-placement='top-end'].show,
.dropdown-menu[x-placement='top-start'].show {
  > :nth-child(1),
  > :nth-child(2),
  > :nth-child(3) {
    animation-name: dropdown-item-show;
  }

  > :nth-last-child(1) {
    animation-name: dropdown-item-show-1;
  }

  > :nth-last-child(2) {
    animation-name: dropdown-item-show-2;
  }

  > :nth-last-child(3) {
    animation-name: dropdown-item-show-3;
  }
}

.dropdown-menu[x-placement='top-end']::before {
  transform-origin: 100% 100%;
}

.dropdown-menu[x-placement='top-start']::before {
  transform-origin: 0 100%;
}

.menu[x-placement='bottom-end']::before {
  transform-origin: 100% ($menu-link-height / 2 + $menu-padding-y);
}

.menu[x-placement='left-start'],
.menu[x-placement='right-start'] {
  margin-top: 0;
}

.menu[x-placement='left-start']::before {
  transform-origin: 100% 0;
}

.menu[x-placement='right-start']::before {
  transform-origin: 0 0;
}

.menu[x-placement='top-end'],
.menu[x-placement='top-start'] {
  margin-top: 0;
  margin-bottom: (($btn-height + $menu-padding-y) * -1 + ($menu-link-height - $btn-height) / -2);
}

.menu[x-placement='top-end']::before {
  transform-origin: 100% calc(100% - #{$menu-link-height / 2 + $menu-padding-y});
}

.menu[x-placement='top-start']::before {
  transform-origin: 0 calc(100% - #{$menu-link-height / 2 + $menu-padding-y});
}

@keyframes dropdown-item-show {
  0% {
    opacity: 0;
  }

  99% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

@keyframes dropdown-item-show-1 {
  0% {
    opacity: 0;
  }

  40% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

@keyframes dropdown-item-show-2 {
  0% {
    opacity: 0;
  }

  60% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

@keyframes dropdown-item-show-3 {
  0% {
    opacity: 0;
  }

  80% {
    opacity: 0;
  }

  100% {
    opacity: 1;
  }
}

@keyframes dropdown-menu-show {
  0% {
    transform: scale(0, 0);
  }

  20% {
    transform: scale((1 / 3), 0);
  }

  40% {
    transform: scale((2 / 3), 0.25);
  }

  60% {
    transform: scale(1, 0.5);
  }

  80% {
    transform: scale(1, 0.75);
  }

  100% {
    transform: scale(1, 1);
  }
}

@keyframes menu-animation {
  0% {
    margin-top: (($menu-link-height + $menu-padding-y) * -1);
  }

  100% {
    margin-top: 0;
  }
}

// Cascading menu for desktop

.dropdown-menu-sm,
.menu-cascading {
  font-size: $menu-font-size-cascading;
  line-height: $menu-line-height-cascading;
  padding-top: $menu-padding-y-cascading;
  padding-bottom: $menu-padding-y-cascading;

  @include media-breakpoint-up(sm) {
    min-width: $menu-min-width-cascading;
  }
}

.menu-cascading {
  margin-top: (($menu-link-height-cascading - ($menu-link-height-cascading - $menu-line-height-cascading) / 2) * -1 + $menu-padding-y-cascading * -1);

  &[x-placement='top-end'],
  &[x-placement='top-start'] {
    margin-top: 0;
    margin-bottom: (($menu-link-height-cascading - ($menu-link-height-cascading - $menu-line-height-cascading) / 2) * -1 + $menu-padding-y-cascading * -1);
  }

  &[x-placement='top-end']::before {
    transform-origin: 100% calc(100% - #{$menu-link-height-cascading / 2 + $menu-padding-y-cascading});
  }

  &[x-placement='top-start']::before {
    transform-origin: 0 calc(100% - #{$menu-link-height-cascading / 2 + $menu-padding-y-cascading});
  }
}

// Divider

.dropdown-divider {
  @include nav-divider($menu-divider-bg);
}

// Header

.dropdown-header {
  color: $menu-header-color;
  display: block;
  font-size: $menu-font-size;
  font-weight: bolder;
  line-height: $menu-line-height;
  margin: 0;
  padding: $menu-link-padding-y $menu-link-padding-x;
  white-space: nowrap;

  .dropdown-menu-sm &,
  .menu-cascading & {
    font-size: $menu-font-size-cascading;
    line-height: $menu-line-height-cascading;
    padding: $menu-link-padding-y-cascading $menu-link-padding-x-cascading;
  }
}

// Link

.dropdown-item {
  @include transition-standard(background-color, color);

  background: none;
  border: 0;
  clear: both;
  color: $menu-link-color;
  display: block;
  font-weight: inherit;
  padding: $menu-link-padding-y $menu-link-padding-x;
  position: relative;
  text-align: inherit;
  transform-origin: 0 0;
  white-space: nowrap;
  width: 100%;

  @include active-focus-hover {
    background-color: $menu-link-bg-hover;
    color: $menu-link-color;
    text-decoration: none;
  }

  &.active {
    background-color: $menu-link-bg-hover;
  }

  &.disabled,
  &:disabled {
    background-color: transparent;
    color: $menu-link-color-disabled;
    pointer-events: none;
  }

  .dropdown-menu-sm &,
  .menu-cascading & {
    padding: $menu-link-padding-y-cascading $menu-link-padding-x-cascading;
  }
}

.dropdown-item-text {
  color: $menu-link-color;
  display: block;
  font-weight: inherit;
  padding: $menu-link-padding-y $menu-link-padding-x;
  transform-origin: 0 0;

  .dropdown-menu-sm &,
  .menu-cascading & {
    padding: $menu-link-padding-y-cascading $menu-link-padding-x-cascading;
  }
}

// Toggle

.dropdown-toggle {
  &::after {
    @include set-material-icons;

    content: $caret-icon;
    display: inline-block;
    margin-right: ($caret-spacer-x * -1);
    margin-left: $caret-spacer-x;
    vertical-align: top;

    .dropright & {
      content: $caret-icon-right;
    }

    .dropup & {
      content: $caret-icon-up;
    }
  }

  &:empty::after {
    margin-left: ($caret-spacer-x * -1);
  }

  .dropleft & {
    &::after {
      display: none;
    }

    &::before {
      @include set-material-icons;

      content: $caret-icon-left;
      display: inline-block;
      margin-right: $caret-spacer-x;
      margin-left: ($caret-spacer-x * -1);
    }
  }
}
